The dhcptab Table

The dhcptab table
contains all the information that clients can obtain from the DHCP server.
The DHCP server scans the dhcptab table each time it
starts. The file name of the dhcptab table varies according
to the data store used. For example, the dhcptab table
created by the NIS+ data store SUNWnisplus is SUNWnisplus1_dhcptab.

The DHCP protocol defines a number of standard items of information
that can be passed to clients. These items are referred to as parameters,
symbols, or options. Options are defined in the DHCP protocol by numeric codes
and text labels, but without values. Some commonly used standard options are
shown in the following table.

Table 12–1 Sample DHCP Standard
Options

Code

Label

Description

1

Subnet

Subnet mask IP address

3

Router

IP address for the router

6

DNSserv

IP address for the DNS server

12

Hostname

Text string for the client host name

15

DNSdmain

DNS domain name

Some options are automatically assigned values when you provide information
during server configuration. You can also explicitly assign values to other
options at a later time. Options and their values are passed to the client
to provide configuration information. For example, the option/value pair, DNSdmain=Georgia.Peach.COM, sets the client's DNS domain name to Georgia.Peach.COM.

Options can be grouped with other options in containers known as macros, which makes it easier to pass information to a client.
Some macros are created automatically during server configuration and contain
options that were assigned values during configuration. Macros can also contain
other macros.

The format of the dhcptab table is described in
the dhcptab(4) man
page. In DHCP Manager, all the information shown in the Options and Macros
tabs comes from the dhcptab table. See About DHCP Options for more information
about options. See About DHCP Macros for
more information about macros.

Note that the dhcptab table should not be edited
manually. You should use either the dhtadm command or DHCP
Manager to create, delete, or modify options and macros.